This disclosure relates to a system for measuring the amount of force applied to an object, and more specifically, this disclosure relates to measuring force with an electromagnetic radiation load measurement system.
Sensors for detecting the amount of force applied to an object are critical for determining the object's useful life. When the object is a beam or girder of a building, bridge, or other structure, or a rail of a railroad track, knowing the amount of time the object has before it is fails is absolutely safety critical.
Measuring the useful life of a rail, for example, has traditionally been a difficult measurement. The two most common problems rails face are metal fatigue leading to structural failure and derailments, and out-of-round defects in wheels which accelerate other fatigue failures due to constant increased vibration. The problem with measuring these forces is the huge load forces, the traveling load (with the rolling of the train wheels at up to 72 mph or more), and geometry of the rail and wheel combination.
Numerous strain gage and load cell solutions, both on the rail car wheel/axle assembly and on the track, have been attempted with various degrees of success and accuracy. These sensors produce a varying voltage (by several different means) proportional to a bending moment or a compression force. Most of the solutions are quite expensive, requiring special trucks on the rail cars, special sections of rail being installed, welding or drilling sensors into rails, etc. This has prevented widespread proliferation of such sensors.